Lesson Planet
Search educational resources
  • Sign In Try It Free
  • AI Teacher Tools
    • Discover Resources Search reviewed educational resources by keyword, subject, grade, type, and more
    • Curriculum Manager (My Content) Manage saved and uploaded resources and folders To Access the Curriculum Manager Sign In or Join Now
    • Browse Resource Directory Browse educational resources by subject and topic
    • Curriculum Calendar Explore curriculum resources by date
    • Lesson Planning Articles Timely and inspiring teaching ideas that you can apply in your classroom
    • Our Story
    • Frequently Asked Questions
    • Testimonials
    • Contact Us
  • Pricing
  • School Access
    • Your school or district can sign up for Lesson Planet — with no cost to teachers
      Learn More
  • Sign In
  • Try It Free
Unknown Angle Proofs—Proofs of Known Facts Lesson PlanUnknown Angle Proofs—Proofs of Known Facts Lesson Plan
Publisher
EngageNY
Resource Details
Curator Rating
Educator Rating
Not yet Rated
Grade
9th - 10th
Subjects
Math
1 more...
Resource Type
Lesson Plans
Audience
For Teacher Use
Duration
45 mins
Instructional Strategies
Discussion
1 more...
Technology
Calculator
Video
Year
2015
Usage Permissions
Creative Commons
BY-NC-SA: 3.0
cc
Language
English, Arabic
Lesson Plan

Unknown Angle Proofs—Proofs of Known Facts

Curated and Reviewed by Lesson Planet
This Unknown Angle Proofs—Proofs of Known Facts lesson plan also includes:
  • Congruence, Proof, and Constructions - Module Overview (PDF)
  • Unknown Angle Proofs—Proofs of Known Facts (Doc)
  • Unknown Angle Proofs—Proofs of Known Facts (PDF)
  • Join to access all included materials

Lead the class in a Greek history lesson with a geometric twist. Pupils relate a short video about geometric properties to modern-day methods of solving for unknown angles. They discuss parallel line theorems and complete practice problems to present before their peers.

13 Views 9 Downloads
CCSS: Designed

Concepts

parallelograms, geometric properties, angles

Additional Tags

math

Instructional Ideas

  • Locate additional video segments to provide further assistance with problem completion for this and previous lessons

Classroom Considerations

  • Present the video upon review of terms but before the class begins practice problems
  • Class should already understand that opposite parallelogram angles are equal in measure before starting this lesson
  • Resource 11 in a 36-part series

Pros

  • Includes a video to assist with integration of concepts presented
  • Contains a detailed explanation of parallel line and converse theorems to ensure complete understanding

Cons

  • None

Common Core

HSG-CO.C.9 MP7

View 38,624 other resources for 9th - 10th Grade Math

© 1999-2026 Learning Explorer, Inc.
Teacher Lesson Plans, Worksheets and Resources

Sign up for the Lesson Planet Monthly Newsletter

Open Educational Resources (OER)

  • Health
  • Language Arts
  • Languages
  • Math
  • Physical Education
  • Science
  • Social Studies
  • Special Education
  • Visual and Performing Arts
View All Lesson Plans

Discover Resources

  • Our Review Process
  • How it Works
  • How to Search
  • Create a Collection

Manage Curriculum

  • Edit a Collection
  • Assign to Students
  • Manage My Content
Contact Us Site Map Privacy Policy Terms of Use